北京城区秋季不同高度积尘中微量元素污染特征及源解析
Characteristics and source analysis of trace element pollution in dust accumulated at different heights in Beijing
祖思达 1张兰 2李杏茹 2董洁 1雷文凯 1赵文吉1
作者信息
- 1. 首都师范大学资源环境与旅游学院,北京,100048
- 2. 首都师范大学化学系,北京,100048
- 折叠
摘要
为研究北京市城区大气积尘中微量元素在不同高度下的污染特征及来源,于2021年9-11月采集了积尘样品,用电感耦合等离子体质谱仪ICP-MS(8800)分析了 11种重金属元素(Mn、Zn、Cu、Cr、Pb、V、Ni、As、Co、Mo、Cd)和14种稀土元素,采用地累积指数法、富集因子法、配分模式图和主成分分析法对其进行污染特征和来源分析.结果表明,11种重金属元素的浓度从低层至中层逐渐升高,低层与高层浓度相差不大,Zn元素浓度从中层至高层呈上升趋势,在高层出现最大值584.3 mg·kg-1,而V、Mn、Ni、Cu等元素浓度从中层至高层降低,14种稀土元素浓度均在中层最低,其浓度在所有高度下均未超出环境背景值.地累积指数结果表明,Cd元素在中层污染最为严重,污染等级为4级,Zn元素在高层污染最为严重,污染等级为2级,而As、Mn、Mo、Co、V污染程度均为无污染,但相对于低层与高层,中层污染指数较高.通过富集因子、配分模式图和主成分分析结果显示,14种稀土元素来源为自然源,11种重金属元素来源为地壳源、交通源和燃烧源.
Abstract
To study the pollution characteristics and sources of trace elements in Beijing's atmospheric dust at different heights,dust samples were collected from November to December,2021,and the contents of 11 heavy metals(Mn,Zn,Cu,Cr,Pb,V,Ni,As,Co,Mo,Cd)and 14 rare earth elements were analyzed by ICP-MS(8800).The results show that the contents of 11 heavy metal elements gradually increase from the lower layer to the middle layer,and the contents of the lower layer and the upper layer are not much different,while the maximum value of Zn element is 584.3 mg·kg-1 in the upper layer,and the concentrations of 14 rare earth elements are all in the middle layer and the bottom region,and their contents do not exceed the environmental background values at all heights.The results of the ground accumulation index show that Cd elements are the most polluted in the middle layer with pollution level 4,Zn elements are the most polluted in the upper layer with pollution level 2,while As,Mn,Mo,Co,V pollution levels are non-polluted,but the pollution index is higher in the middle layer compared to the lower and upper layers.The results of enrichment factors and principal component analysis show that 14 rare earth elements are from crustal sources and 11 heavy metals are from crustal,traffic and combustion sources.
关键词
积尘/不同高度/重金属/稀土元素/污染特征/来源Key words
dust accumulation/different heights/heavy metals/rare earth elements/pollution characteristics/sources引用本文复制引用
基金项目
国家自然科学基金(42071422)
北京市自然科学基金(8153036)
出版年
2024
NETL
NSTL
万方数据